/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.zookeeper.server;

import java.io.File;
import java.io.IOException;

import javax.management.JMException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.zookeeper.jmx.ManagedUtil;
import org.apache.zookeeper.server.persistence.FileTxnSnapLog;
import org.apache.zookeeper.server.quorum.QuorumPeerConfig.ConfigException;

/**
 * This class starts and runs a standalone ZooKeeperServer.
 */
public class ZooKeeperServerMain {
	private static final Logger LOG = LoggerFactory.getLogger(ZooKeeperServerMain.class);

	private static final String USAGE = "Usage: ZooKeeperServerMain configfile | port datadir [ticktime] [maxcnxns]";

	/*
	 * Start up the ZooKeeper server.
	 *
	 * @param args the configfile or the port datadir [ticktime]
	 */
	public static void main(String[] args) {
		ZooKeeperServerMain main = new ZooKeeperServerMain();
		try {
			main.initializeAndRun(args);
		} catch (IllegalArgumentException e) {
			LOG.error("Invalid arguments, exiting abnormally", e);
			LOG.info(USAGE);
			System.err.println(USAGE);
			System.exit(2);
		} catch (ConfigException e) {
			LOG.error("Invalid config, exiting abnormally", e);
			System.err.println("Invalid config, exiting abnormally");
			System.exit(2);
		} catch (Exception e) {
			LOG.error("Unexpected exception, exiting abnormally", e);
			System.exit(1);
		}
		LOG.info("Exiting normally");
		System.exit(0);
	}

	private ServerCnxnFactory cnxnFactory;

	protected void initializeAndRun(String[] args) throws ConfigException, IOException {
		try {
			ManagedUtil.registerLog4jMBeans();
		} catch (JMException e) {
			LOG.warn("Unable to register log4j JMX control", e);
		}

		ServerConfig config = new ServerConfig();
		if (args.length == 1) {
			config.parse(args[0]);
		} else {
			config.parse(args);
		}

		runFromConfig(config);
	}

	/**
	 * Run from a ServerConfig.
	 * 
	 * @param config ServerConfig to use.
	 * @throws IOException
	 */
	public void runFromConfig(ServerConfig config) throws IOException {
		LOG.info("Starting server");
		try {
			// Note that this thread isn't going to be doing anything else,
			// so rather than spawning another thread, we will just call
			// run() in this thread.
			// create a file logger url from the command line args
			ZooKeeperServer zkServer = new ZooKeeperServer();

			FileTxnSnapLog ftxn = new FileTxnSnapLog(new File(config.dataLogDir), new File(config.dataDir));
			zkServer.setTxnLogFactory(ftxn);
			zkServer.setTickTime(config.tickTime);
			zkServer.setMinSessionTimeout(config.minSessionTimeout);
			zkServer.setMaxSessionTimeout(config.maxSessionTimeout);
			cnxnFactory = ServerCnxnFactory.createFactory();
			cnxnFactory.configure(config.getClientPortAddress(), config.getMaxClientCnxns());
			cnxnFactory.startup(zkServer);
			cnxnFactory.join();
			if (zkServer.isRunning()) {
				zkServer.shutdown();
			}
		} catch (InterruptedException e) {
			// warn, but generally this is ok
			LOG.warn("Server interrupted", e);
		}
	}

	/**
	 * Shutdown the serving instance
	 */
	protected void shutdown() {
		cnxnFactory.shutdown();
	}
}
